Systems and processes

Question 1

Name some factors which affect wave energy:

Answer 1

• Strength of the wind
• Duration of the wind
• Fetch

Question 2

Describe tides

Answer 2

Changes in the water level of the sea/ocean caused by the gravitational pull of the moon.

Question 3

Define tidal range

Answer 3

Difference between high and low tides

Question 4

Define rip currents

Answer 4

Strong localised underwater currents

Question 5

How are rip currents formed?

Answer 5

When a series of plunging waves caused a build-up of water at the top of the beach. The backwash is forced below the surface.

Question 6

Give some landforms found in high-energy environments

Answer 6

Headlands
Cliffs
Wave-cut platforms
Rocky coasts

Question 7

High-energy environments are found:

Answer 7

• Along stretches of the Atlantic-facing coast; powerful waves all year
• Where the rate of erosion exceeds the rate of deposition

Question 8

Give some landforms found in low-energy environments

Answer 8

Beaches
Spits
Sandy coasts

Question 9

Low-energy environments are found:

Answer 9

• Along stretches of the coast where the waves are less powerful
• Where the rate of deposition exceeds the rate of erosion

Question 10

Name some sediment sources:

Answer 10

Rivers
Cliff erosion 
longshore drift 
Wind 
Glaciers

Question 11

What is a sediment cell?

Answer 11

A stretch of coastline where the movement of sediment is contained.

Question 12

Give an example of an input, transfer and store in a sediment cell:

Answer 12

Input - Costal erosion
Transfer - Longshore drift
Store - Sand dunes

Question 13

Define sediment budgets

Answer 13

Material in a sediment cell

Question 14

What does the sediment budget aim to do?

Answer 14

Maintain a state of dynamic equilibrium; erosion and deposition balanced.

Question 15

Describe the types of mechanical weathering

Answer 15

• Freeze-thaw: water enters cracks in rock, freezes and expands putting pressure on the rock and causing it to break off
• Wetting and drying: rocks expand when they get wet and contract as they dry, causing them to crack
• Salt crystallisation: water evaporates leaving salt crystals behind, these can grow overtime exerting pressure on the rock

Question 16

Describe the types of biological weathering

Answer 16

• Plant roots (seaweed) grow through small cracks, widening these as they grow
• Bird and animals burrowing
• Algae secrete chemicals, promoting solution

Question 17

Describe the types of chemical weathering

Answer 17

• Carbonation: rainwater absorbs carbon dioxide, forming a weak acid which reacts with calcium carbonate in rocks
• Oxidation: reaction of rocks with oxygen, leaving them vulnerable to more weathering
• Solution: dissolving of rock minerals

Question 18

Describe the process of mass movement

Answer 18

The downhill movement of material under the influence of gravity

Question 19

Give some examples of mass movement

Answer 19

Mudflows
Landslide
Rockfall
Soil creep

Question 20

Describe the types of costal erosion:

Answer 20

• Hydraulic action: sheer force of water entering cracks in the rock
• Corrasion/Abrasion: sediment hurled at the cliff face/ dragged along the cliff
• Solution: weak acids dissolve alkaline rock

Question 21

Describe the types of costal transportation processes:

Answer 21

• Traction: rolling of sediment along the seabed which is too heavy to be carried by the sea
• Saltation: sediment bounces along the seabed, light enough to be lifted but not carried
• Suspension: lighter sediment picked up and carried within the flow of water

Question 22

What factors effect the type of transpiration seen at a costal environment?

Answer 22

Velocity (energy)

Particle size

Question 23

Describe the process of longshore drift:

Answer 23

Waves approach the beach at an angle, carrying material up the beach. The backwash pulls the sediment vertically down (perpendicular to the beach front). This results in a zigzag movement of sediment along the beach.

Question 24

Describe the process of costal deposition:

Answer 24

Deposition occurs when the velocity of the water can no longer transport particles of a certain size.

Question 25

Describe the process of deposition in a high-energy environment:

Answer 25

Clay and sand is transported away leaving behind larger, coarser pebbles to form a shingle beach.

Question 26

Describe the process of deposition in a low-energy environment:

Answer 26

Small clay particles will drop to the seabed to form mudflats.

Question 27

What is upwelling?

Answer 27

Cold water from deep in the ocean moves towards the surface

Question 28

What factors effect the rate of erosion at a coastline?

Answer 28

Rock type Beaches - absorb wave energy Weathering and mass movement - weakening cliff and producing rock fragments Waves - time of year